Conducting interdisciplinary teaching is of great significance and value to primary school general subject teachers. This study takes 63 in-service primary school general subject teachers as typical cases and adopts a mixed research method. Some conclusions are found: in terms of beliefs, primary school general subject teachers agree with the value of interdisciplinary teaching, but have insufficient understanding of the connotation of interdisciplinary teaching. In terms of implementation, it is generally believed that interdisciplinary teaching is difficult and the implementation is often a shallow approach of “passing through one step at a time”. In terms of effectiveness, the lack of interdisciplinary teaching evaluation is difficult to meet the good expectations for interdisciplinary teaching effectiveness. Research suggests that the reasons for the above problems are the constraints of traditional interdisciplinary teaching concepts, weak knowledge foundation in interdisciplinary teaching, and insufficient interdisciplinary teaching conditions. Regarding the cultivation of interdisciplinary teaching literacy for primary school general practitioners, research suggests that the education departments need to increase the guidance of interdisciplinary teaching concepts and promote primary school general practitioners to actively change their teaching concepts. Universities need to reform the training mode of primary school general subject teachers and optimize the interdisciplinary knowledge structure of primary school general subject teachers. Schools need to provide interdisciplinary teaching resources, improve interdisciplinary teaching and research mechanisms, and accumulate experience in interdisciplinary teaching for primary school general practitioners.